Scala example source code file (MutableSettings.scala)

This example Scala source code file (MutableSettings.scala) is included in my "Source Code Warehouse" project. The intent of this project is to help you more easily find Scala source code examples by using tags.

All credit for the original source code belongs to scala-lang.org; I'm just trying to make examples easier to find. (For my Scala work, see my Scala examples and tutorials.)

Scala tags/keywords

boolean, booleansetting, intsetting, multistringsetting, mutablesettings, setting, settingvalue, t, yposdebug, yshowsymkinds

The MutableSettings.scala Scala example source code

/* NSC -- new Scala compiler
 * Copyright 2005-2013 LAMP/EPFL
 * @author  Martin Odersky
 */
// $Id$

package scala
package reflect.internal
package settings

/** A mutable Settings object.
 */
abstract class MutableSettings extends AbsSettings {

  type Setting <: SettingValue
  type BooleanSetting <: Setting { type T = Boolean }
  type IntSetting <: Setting { type T = Int }
  type MultiStringSetting <: Setting { type T = List[String] }

  // basically this is a value which remembers if it's been modified
  trait SettingValue extends AbsSettingValue {
    protected var v: T
    protected var setByUser: Boolean = false

    def postSetHook(): Unit = ()
    def isDefault = !setByUser
    def isSetByUser = setByUser
    def value: T = v
    def value_=(arg: T) = {
      setByUser = true
      v = arg
      postSetHook()
    }
  }

  def Xexperimental: BooleanSetting
  def XfullLubs: BooleanSetting
  def XnoPatmatAnalysis: BooleanSetting
  def Xprintpos: BooleanSetting
  def strictInference: BooleanSetting
  def Yposdebug: BooleanSetting
  def Yrangepos: BooleanSetting
  def Yshowsymowners: BooleanSetting
  def Yshowsymkinds: BooleanSetting
  def breakCycles: BooleanSetting
  def debug: BooleanSetting
  def developer: BooleanSetting
  def explaintypes: BooleanSetting
  def overrideObjects: BooleanSetting
  def printtypes: BooleanSetting
  def uniqid: BooleanSetting
  def verbose: BooleanSetting

  def Yrecursion: IntSetting
  def maxClassfileName: IntSetting

  def isScala211: Boolean
}

object MutableSettings {
  import scala.language.implicitConversions
  /** Support the common use case, `if (settings.debug) println("Hello, martin.")` */
  @inline implicit def reflectSettingToBoolean(s: MutableSettings#BooleanSetting): Boolean = s.value
}